1. Field of the Disclosure
The present invention relates generally to application-specific integrated circuits, and more specifically, the present invention is directed to global routing channels in application-specific integrated circuits.
2. Background
Application-specific integrated circuits are integrated circuits that can be customized for specific uses or applications. In semiconductor design, digital standard cells are the building blocks that are used to design application-specific integrated circuits with digital logical functions.
Global routing between the standard cells in application-specific integrated circuits is required to complete logical functions. To increase the feasibility of routing throughout the entire chip, global routing channels between the standard cells of application-specific integrated circuits are sometimes needed, especially for those microchips that have fewer metal layers of routing. However, the global routing channels can decrease the fill ratio of standard cells in the application-specific integrated circuits as a consequence of the chip real estate that is occupied by the global routing channels. A low fill ratio can present serious challenges in semiconductor designs, such as for example increased chip sizes, higher costs, and lower circuit speeds.
Corresponding reference characters indicate corresponding components throughout the several views of the drawings. Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention.